Anthropologists have traditionally inferred the diet of ancient human ancestors by looking at the size and shape of the teeth and jaws. However, by using powerful microscopes to look at the patterns of wear on a tooth, scientists can get direct evidence of what the species actually ate.
Since food interacts with teeth, it leaves behind telltale signs that can be measured. Hard foods like nuts and seeds, for instance, lead to more complex tooth profiles, while tough foods like leaves lead to more parallel scratches.
Researchers compared dental microwear profiles of P. boisei to modern-day primates that eat different types of foods. P. boisei teeth were compared to those of the Old World Monkey species grey-cheeked mangabeys, and the New World Monkey species brown capuchin monkeys--both of these species consume mostly soft items but fall back on hard nuts or palm fronds.
Old World monkeys are found today in South and East Asia, the Middle East, Africa and Gibraltar at the southern tip of Spain. New World monkeys are found in tropical forest environments in southern Mexico, Central and South America.
P. boisei dental profiles also were compared to the New World mantled howling monkey and Old World silvered leaf monkey, which eat mostly leaves. Researchers also compared them to some of P. boisei's more contemporary counterparts--Australopithecus africanus, which lived between 3.3 million and 2.3 million years ago, and Paranthropus robustus, which lived between 2 million and 1.5 million years ago.
The findings showed that P. boisei teeth had light wear, suggesting that none of the individuals ate extremely hard or tough foods in the days leading up to death. The pattern was more consistent with modern-day fruit-eating animals than with most modern-day primates.
"It looks more like they were eating Je
|Contact: Bobbie Mixon|
National Science Foundation